The idea behind XMLHttpRequest was originally created by Microsoft in 1999 as part of the Outlook Web Access for Microsoft Exchange 2000. The intention was to provide a highly interactive UI similar to the Microsoft Outlook but being based on a Web Browser. In 2002 the Mozilla Foundation launched Mozilla 1.0 which provided a Javascript object that is compatible with Microsoft XMLHttpRequest. In 2004, Gmail was launched that uses XMLHttpRequest to implement highly interactive user interface and it worked in almost all browsers. Later in 2006, Jesse James Garret coined the term AJAX (Asynchronous Javascript Aand XML) that refers to the technique used by Web Applications to send and receive information from the web server using XMLHttpRequests.

The main limitation of this object is that it can’t access remote servers. This is mainly because of the ‘same-origin policy’ that exists to prevent malicious use of resources. Another limitation is that uploading files is not possible using the current version of XMLHttpRequest object due to security reasons.

The above mentioned limitations are addressed in the latest version of XMLHttpRequest object (the specification is still a draft) and some interesting aspects that are worth commenting are as follows:

• Can make cross-origin requests.
• Progress events for uploading and downloading
• Ability to stream large amounts of data like BLOB, File etc to and from the client
• Can override the media type and encoding of the response using overrideMimeType() method
• Ability to make anonymous requests
• Can set timeout for the request

A positive point to note about this is that at least now there is a specification that all browser companies are expected follow. Else we have to write that extra lines of code to detect browser type and version to make our code work consistently across different browsers.

References:

http://dev.w3.org/2006/webapi/XMLHttpRequest-2/

http://www.adaptivepath.com/ideas/essays/archives/000385.php

The main goal is to collect, upload and show patient interviews about their illnesses and experience.

Uploaded interviews videos are stored in Flash Media Server for streaming and all interviews are displayed categorized by disease group, condition and symptoms.

Data importing involved conversion of over 15,000 windows media video files to flash format and importing of existing data from old to new database using complex sql queries and cursors.

Technologies:

ASP.NET 2 C#, SQL Server 2005, ASP.NET AJAX, Flash CS3, Flash Media Server
and jquery.

Technology features:

• Object Oriented Programming with layered architecture – for
• extensibility and easy maintenance.
• AJAX based CMS and Front end – Easy and comfortable user experience,
• less page post backs.
• Front end navigations and styles are manageable through CMS.
• Dynamic creation of CSS using template and Regular expression for each
• disease group.
• Video streaming using Flash Media Server
• URL Rewriting – for readable urls and search engine optimization

The Spry framework from Adobe is a way to incorporate XML, JSON or HTML data into pages using HTML, CSS, and a minimal amount of JavaScript, without the need for refreshing the entire page. Spry also provides easy to build and style widgets, providing advanced page elements for end users. Need to investigate whether Spry would support Zeldman design.